Module suspension system

ABSTRACT

A support system for supporting a plurality of vertically stacked modules which will permit selective future disassembly of individual modules therefrom. The support system comprises a pair of parallel spaced horizontal support means with a plurality of vertical supports spaced along, extending from and supported by the horizontal support means. Sets of retaining means and respective resting surfaces are mounted on the vertical supports so as to form at least two levels of holding assemblies, one above the other, for supporting the individual vertically stacked modules. One side of each module is supported between a set of retaining means and a respective set of resting surfaces of one horizontal support means and the other side is supported between the corresponding set of retaining means and resting surfaces of the other horizontal support means. For ease in disassembly, at least one of the sets of retaining means and its respective resting surfaces are vertically movable relative to one another for release of the individual module held therebetween.

United States Patent [191 Hurlbut, Sr. et al.

[ 1 Mar. 11, 1975 1 MODULE SUSPENSION SYSTEM [75] Inventors: William Barrett Hurlbut, Sr., East Hartford; Preston Dean Liebig, West Hartford; Gerald Maurin, Newington, all of Conn.

[73] Assignee: Combustion Engineering, Inc.,

Windsor, Conn.

[22] Filed: June 28, 1972 [21] Appl. No.: 266,852

52 user ..55/436,55/440,55/484,

248/58 51 Int. Cl. ..B0ld45/08 58 Field of Search 55/185, 186, 440-444,

[56] References Cited UNITED STATES PATENTS 2,583,171 1/1952 Green et a1. 55/444 2,689,630 9/1954 Drury 52/664 3,360,910 l/1968 Soltis 55/484 3,740,934 6/1973 Shuler 98/40 D Primary Examiner-Bernard Nozick Attorney, Agent, or Firm-John R. Nelson [57] ABSTRACT A support system for supporting a plurality of vertically stacked modules which will permit selective future disassembly of individual modules therefrom. The support system comprises a pair of parallel spaced horizontal support means with a plurality of vertical supports spaced along, extending from and supported by the horizontal support means. Sets of retaining means and respective resting surfaces are mounted on the vertical supports so as to form at least two levels of holding assemblies, one above the other, for supporting the individual vertically stacked modules. One side of each module is supported between a set of retaining means and a respective set of resting surfaces of one horizontal support means and the other side is supported between the corresponding set of retaining means and resting surfaces of the otherhorizontal support means. For ease in disassembly, at least one of the sets of retaining means and its respective resting surfaces are vertically movable relative to one another for release of the individual module held therebetween.

7 Claims, 6 Drawing Figures PATENTEU 1 I975 SHEET 3 9F 3 FIG.

FIG. 6

MODULE SUSPENSION SYSTEM BACKGROUND OF THE INVENTION This invention relates to a support system for supporting a plurality of individual vertically stacked modules and more particularly to a support system which will afford easy accessibility for future selective disassembly of the modules. Such a system has particular application for the suspension of demister modules in an air pollution control system.

One of the primary contributions to air pollution occurs with the combustion of fossil fuels for the purpose of power generation wherein the flue gases resulting from the combustion process contain both particulate matter and certain gaseous compounds which are generally injurious to health and damaging to physical property. Systems have been developed for substantially reducing this pollution and generally involve the reacting of pulverized additives with the combustion gases to form compounds which are then washed from the flue gases in a wet scrubber. Water is added in the scrubber to enhance the formation of pollutant compounds and to entrain particulate matter such as fly ash in the gases. Often, as the gases leave the scrubber, they still contain some water which in turn contains some of the particles and reactive compounds. Accordingly, it is necessary to pass the gas through a demister system to efficiently remove from the gases the water and pollutants contained therein. However, thevery action of water collection which the demister is to provide, promotes the deposit of particulate matter and other corrosive products on the demisters. If enough deposit builds up on the demister assembly, the demister will foul up and the efficiency of the system will be lowered.

Efficient water removal from the flue gases has, in the past, been accomplished by providing a plurality of levels of demisters in which the gases must traverse a tortuous path through each level of demisters. Commonly, each level of the demister assembly is con-v structed from a plurality of individual demister modules arranged in a series of rows across the interior of the gas path. Use of modules yields the advantages of shop optimization such as being adaptable to a variety of geometric configurations of the gas path and also easy field assembly of the demister system. Finally, in order to overcome the problem of pollutant buildup on the demister, it is often necessary to disassemble the demister system and remove it from the scrubber to efficiently clean the demister modules.

SUMMARY OF THE INVENTION Accordingly, it is herein provided a support system for supporting a plurality of individual vertically stacked modules which will permit selective future disassembly of the individual modules from the support system. Generally the support system comprises a pair of parallel spaced horizontal support means with a plurality of vertical supports spaced along, extending from and supported by the horizontal support means. A plurality of retaining means are mounted on the vertical supports so as to form a first set of retaining means at a first vertical elevation relative to the horizontal support means and a second set of retaining means at a second vertical elevation below the first vertical elevation. A first set of resting surfaces for the first set of retaining means are mounted on some of the vertical supports at a vertical elevation between the first and second vertical elevations and a second set of resting surfaces for the second set of retaining means are mounted on some of the vertical supports at a vertical elevation below the second vertical elevation. Each of the sets of retaining means and its respective set of resting surfaces form a level of holding assemblies, one above the other, for supporting the individual vertically stacked modules, one side of each module being supported between the retaining means and its respective resting means of one horizontal support means and the other side being supported between the corresponding retaining means and resting surfaces of the other horizontal support means. For ease in disassembly, at least one of the sets of retaining means and its respective resting surfaces are vertically movable relative to one another for release of the individual module held therebetween.

Such a support system has particular application in an air pollution control system which has a demister assembly comprised of a plurality of individual vertically stacked demister modules. During the life of the demister assembly, when it becomes necessary to clean some or all of the modules of the corrosive product buildup, the modules needed to be cleaned may be simply and selectively disassembled. Also such a support system provides the advantages of easy inspection of the demister modules to see if cleaning is necessary and the advantage of shop optimized manufacturing of both the modules and the support system. Further after being shop manufactured the assembly may be simply field assembled.

It should be apparent that although this invention was designed for supporting demister assemblies, it may of course be utilized to support any type of assembly having a plurality of vertically stacked modules in which it is desirous to be able to selectively disassemble a portion of or all of the modules. Such a support system might find application in filter systems wherein it is necessary to periodically replace the filters or possibly in shelving for storage systems wherein articles are stored on shelves which are then placed in the storage system and which may be selectively taken therefrom when needed at some time in the future.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view, partially cut away for clarity, of a demister system supported by the present invention;

FIG. 2 is an enlarged perspective view of a portion of the suspension system of FIG. 1 wherein the demister modules have been removed for clarity;

FIG. 3 is a side elevation view of the portion of the support system of FIG. 2;

FIGS. 4 through 6 are side elevational views, similar to that of FIG. 3, of alternative embodiments for the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to the figures wherein like reference characters represent like elements, FIG. 1 shows ademister assembly 10 having a plurality of demister modules 12 for use in a typical air pollution control system. The assembly 10 will be placed in the gas passageway downstream of the wet scrubber with the modules 12 being arranged so as to substantially cover or block the entire flow area therethrough. In this way virtually all of the flue gases, with water and pollutant particles entrained therein, will impinge on the demister modules 12 after passing through the wet scrubber. The demister system shown in FIG. 1 is comprised of three rows of three demister modules 12 each and is thus suitable for a gas passageway having dimensions substantially equivalent to the width of three demister modules and substantially equivalent to the length of three modules. Also shown therein are two levels of modules 12, one directly above the other which have been employed to facilitate and insure efficient water and pollutant particle removal from the flue gases. Each of the modules 12 is chevron shaped and is constructed of a plurality of vanes 18, each vane providing a flow diverting surface to initiate water and particle removal as the gas impinges thereon. Typical shapes which have been utilized for the flow diverting surfaces of the vanes 18 are Z-shaped cross sections or V-shaped cross sections. The vanes 18 each meet at a central plate 16 which forms the apex of the chevron and each have side plates 14 attached at the lower and remote ends thereof. This arrangement for each of the modules 12 provides adequate structural strength such that the modules may be supported solely by the end plates 14. The construction of the modules as described above forms no part of the present invention but is merely for descriptive purposes. Instead, the present invention is directed to a means for supporting such a demister assembly 10.

Accordingly, there is provided a support system for supporting the modules 12 and which will permit future disassemblyof a part of the modules without having to remove or disassemble all the modules in the air pollution control system. This is particularly advantageous since it is highly unlikely, due to flow fluctuations and variations through the gas passage, that all of the modules will become caked or clogged with pollutant deposition at the same rate, thereby necessitating cleaning of all modules at one time. The support system comprises a plurality of horizontal, longitudinally extending, support means 20 which are parallel to each other and which extend across the passageway of the air pollution control system, transverse to the gas flow path. The lateral spacing between each of the horizontal support means 20 is substantially equal to the width of the demister modules 12 such that each of the modules 12 is supported between a pair of horizontal support means. Spaced along and supported by the horizontal support means 20 are a plurality of vertical support means 26, 32, 34 which extend downward therefrom parallel to the direction of gas flow. Retaining means 28, 30, and resting means 36, 38 are disposed on various vertical support means 26, 32, 34 at various vertical elevations from the horizontal support means 20 to form a plurality of upper and lower holding assemblies which support and retain the sides of the modules having side plates 14. Generally the vertical support means 26, 32, 34 which form the structure of one set of holding assemblies are grouped together and the groups of supports are spaced along the longitudinal length of the horizontal support means 20 in pairs so as to provide support for one of the lateral sides ofa module at both the left and right longitudinal edges thereof. The groups of vertical support means 26, 32, 34 for supporting the other modules 12 from the same horizontal support means 20, are similarly grouped in pairs and the pairs of supports arranged so that the longitudinal ends of the modules will abut one another.

The detailed construction of the horizontal support means 20 and the various vertical support means for the preferred embodiment is best seen in FIGS. 2 and 3 which depict one set of holding assemblies extending from the horizontal support means 20. The horizontal support means 20 comprises two channel beams 22, 24 which are laterally spaced from one another a small distance so as to provide an opening therebetween. The group of vertical support means 26, 32, 34 forming the structure of the holding assembly extend downwardly from this opening and are arranged in two sets along the horizontal support means as described hereinabove. For the one set of holding assemblies shown in FIG. 2 each of the two vertical support bars 26 is welded at one end between the channel beams 22, 24. At the other end two retaining clips 28, 30 are integrally attached at a first vertical elevation from the horizontal support means 20. Retaining clips 28, 30 extend outwardly from the bar 26 in opposite directions and terminate in downwardly extending edges. As shown in this embodiment, the clip 28 is formed with the bar 26 and the clip 30 then integrally attached thereto at the same vertical elevation such as by welding. The other vertical support bars 32 and 34 shown in FIG. 2 extend downward from the horizontal support means 20 to an elevation lower than the first vertical support bars 26 and are also arranged in pairs oflike elements along the longitudinal length of the horizontal support means 20, one such pair of each of the vertical support bars 32, 32 and 34, 34 forming part of the one set of holding assemblies shown in FIG. 2. Each of the bars 32, 34 extends through the opening between the channel beams 22, 24 and is supported from above by a retaining pin 42 which passes through a slot in the bars 32, 34. The pin 42 spans the lateral opening between the beams 22, 24. A hole 44 in each of the bars 32, 34 is provided for initially lifting the bars into place. Each of the pairs of like vertical support bars 32, 32 and 34, 34 have integrally attached on one side thereof an upper resting rail 36, two retaining clips 40 and a lower resting rail 38. The two resting rails 36, 38 are each attached to both of the like vertical support bars 32, 32 and 34, 34 and thus set the longitudinal spacing therebetween. The upper retaining rail 36 is positioned at a second vertical elevation below that of the first vertical elevation of the retaining clips 28, 30 and the lower retaining rail 38 is positioned at a third vertical elevation below that of both the first and second vertical elevations. Both the rails 36 and 38 are parallel to one another and parallel to the horizontal support means 20 so that they provide a level horizontal resting surface for the modules 12. The two retaining clips 40, one for each of the like vertical support bars 32, 32 and 34, 34 are positioned at a fourth vertical elevation between the second vertical elevation of the upper resting rail 36 and the third vertical elevation of the lower resting rail 38. The vertical spacing between the upper retaining clips 28, 30 and the upper resting rail 36 and the spacing between the retaining clips 40 and a lower resting rail 28 is substantially equal to the vertical height of the side plates 14' of the modules 12 so that the sides of the modules will be retained between a pair of retaining clips at the top and a restingrail at the bottom. Saying this in another way, the sides of each of the'modules 12 will rest on a resting rail end 36 or 38 and be restrained from vertical and laterally outward movement at the top by the resting rails respective retaining clips either 28, 30 or 40.

For this preferred embodiment, it should be noted that each of the pairs of like vertical support bars 32, 32 and 34, 34 are constructed identically. However, when the pairs of support bars are positioned for support from the horizontal support means 20, the resting rails 36, 38 and the retaining clips 40 for the pair 32, 32 and the pair 34, 34 extend outward from the bars in opposite directions. That is, viewing the supporting system of FIG. 2 from the left end, the rails 36, 38 and the clips 40 extend to the left for the vertical support bars 32, 32 while the rails 36, 38 and the clips 40 extend to the right for the vertical support bars 34, 34. In this way the sides of four modules may be supported by the holding assemblies as shown in FIG. 2, two modules, one stacked above the other, extending laterally outward from one side of the horizontal support means 20 and two modules, one stacked above the other, extending laterally outward in the opposite direction from the opposite side of the horizontal support means 20.

In order to provide a complete support system for a plurality of demister modules arranged in rows and transversely stacked one above the other, it is merely necessary to provide a plurality of horizontal support means 20 and a plurality of groups of vertical support means 26, 32, 24. Such a system is shown in FIG. 1 wherein there are two levels of demister modules 12, each level consisting of three rows of three modules each. For supporting such an arrangement of demister modules there are provided four horizontal support means 20 which are parallel and laterally spaced a distance substantially equal to the width of the modules 12. Each horizontal support means 20 is provided with a plurality of vertical support means 26, 32, 34 to form three sets of holding assemblies spaced along the longitudinal length of the horizontal support means so that the three modules 12 in each row will abut one another. For the outer two horizontal support means 20, since no modules will be extending laterally outward therefrom, it is not necessary to provide extra sets of vertical supports 32 on one side or vertical supports 34 on the other side.

Selective future disassembly of the modules '12 for the demister assembly is accomplished by first pro viding a nylon sling or some other similar means to tightly hold a module 12 in the upper level of modules against its respective retaining clips 28 and 30, the clips 28 extending from one horizontal support means and the clips extending from another horizontal support means 20. The module is thus supported between the two horizontal support means 20. Secondly, the retaining pins 42 are removed from each of the pairs of vertical support bars 32, 32 and 34, 34 which hold the lower module 12 lying vertically below the retained upper module 12. Finally, the lower module 12 and the vertical support bars 32, 32 and 34, 34 are then lowered and removed from the assembly with the upper module 12 retained in place against the retaining clips 28 and 30 by the nylon sling or other support means. The lower module 12 held in place between the retaining clips 40 and the lower resting rails 38 of the vertical support bars 32, 32 and 34, 34 is simply removed therefrom by sliding, longitudinally, the module from between the clips 40 and the rails 38. If it is necessary or desirous to remove the upper module 12 also, the sling or other similar support means may be disengaged and the module 12 then lowered and removed from the demister assembly 10. The removed modules 12 are either cleaned and replaced in the demister assembly or simply replaced with new, unused spare modules. The assembling of the clean modules and the demister assembly again is merely accomplished by the reverse operation for disassembly. The upper modules 12 are held in place by a sling and the vertical support bars 32, 32 and 34, 34, with the lower module in place between its retaining clips and lower rails 38, are raised into position and retained by the retaining pins 42. Since each module 12 is supported at each side by just one holding assembly it is not necessary to remove all modules in order to clean or replace damaged demister modules.

FIGS. 4, 5 and 6 show other embodiments for the arrangements of vertical support means, retaining means and resting means for providing holding assemblies which allow easy selective future disassembly of the modules therefrom. In all of these alternate embodiments only one type of vertical support means having a plurality of retaining means and resting means disposed thereon is needed. This is in contrast to the arrangement of the preferred embodiment wherein two types of vertical support means are used, short vertical support bars 26 and long vertical support bars 32 and 34. For each of these alternative embodiments a plurality of vertical support rods 54 extend through the lateral openings between the two channel beams 22, 24 which form a horizontal support means 20. The rods 54 are supported therefrom by means of a washer which extends across the opening between the two channel beams 22, 24 and which is interposed between the top surface of the channel beams and a nut 52 threaded onto the rod 54. The vertical elevation of the rods is set by the nut 52 which may be screwed either up or down to correctly vertically orient each rod 54. As with the preferred embodiment, the longitudinal spacing of the rods along the horizontal support means 20 is such so as to provide support at least at both the left and right ends of each side of the modules 12. The other common feature for these alternative embodiments is that the retaining means and resting means are provided by U-shaped channel washers which are disposed and positioned on the rods 54 to provide holding assemblies.

For the embodiment depicted in FIG. 4, two channel washers and 62 are integrally attached to the rod 54 in a fixed vertical relation to one another, the upper washer 60 being positioned with upwardly extending edges to provide an upper resting surface and the lower washer 62 positioned with downwardly extending edges to provide a lower retaining means. A third channel washer 56 is positioned on the rod 54 above the fixed washer 60 with downwardly extending edges to provide an upper retaining means for the resting surface of the washer 60 and a fourth channel washer with upwardly turned edges is positioned on the rod 54 below the fixed washer 62 to provide a lower resting surface for the lower retaining means 62. The. modules 12 are thus held between respective retaining and resting means 56, 60 and 62, 64 by means of nuts 58 and 59 forcing the upper washer 56 downwardly and the lower washer upwardly respectively. For selective disassembly of the modules from the support system, the upper modules 12 may be removed from above the support system by loosening the nut 58 and the lower modules 12 may be removed from below the system by loosening the nut 59.

The embodiment shown in FIG. is similar to that shown in FIG. 4 except that the vertical spacing of the washers and thus the modules, is controlled by means of spacers 68 and 76. The elevation of the upper modules is set by the spacer 68 which is disposed between the lower surface of the channel beams 22, 24 and the top surface of washer 70, the washer 70 being integrally attached to the rod 54 so as to provide downwardly extending edges. The other channel washers 72, 76 and 78 are disposed on the rod 54 to provide an upper resting surface, a lower retaining means and a lower resting surface respectively, the vertical spacing between the washers 72 and 76 being set by spacer 74. The modules are held in place between respective retaining means at the top and resting means at the bottom 70, 72 and 76, 78 by means ofa nut 59 forcing the washers 78, 76, 72, spacer 74 and modules 12 upward against the fixed washer 70. Selective future disassembly of the modules from a support system utilizing this embodiment is accomplished by a method similar to that used for the preferred embodiment. The upper modules are held against the channel washer 70 by means of a sling, and the lower modules are removed by loosening the nut 59, which releases'the spacer 74, the washers 72, 76, 78 and the modules held between washers 76 and 78. If it is necessary to remove the upper modules, the sling is simply disengaged and the modues 12 released.

For the embodiment shown in FIG. 6, use is made of plastic channel washers instead of metal washers as used in other embodiments. Again, a spacer 82 is used to set the vertical height of the upper retaining washer 84 and thus the level of the upper modules 12, the washer 84 and spacer 82 being held in place by means of a nut 86. A double-ended channel washer 88 is used to provide a resting surface for the upper level of modules and a retaining means for the lower level of modules and a third washer 90 with upwardly extending edges is used to provide a lower resting surface for the lower modules. The double washer .88 is held in place by a nut 86 and the third washer 90, is held in place by a nut 52, the nut 86 maintaining an upward force on the double-ended washer 88 so, that the upper modules will be retained in place when the lower modules are removed. Thus for selective disassembly of the modules from a demister support system utilizing this embodiment, there is no need for a sling to hold the upper modules while lower modules are being removed. Other than this fact, disassembly of the modules is accomplished in the same manner as for the preferred embodiment and the alternative embodiment shown in FIG. 5.

It should be noted that use of the embodiments shown in FIGS. 4, 5 and 6 to support a plurality of individual and vertically stacked modules which extend laterally outward from both sides of a horizontal support means will necessitate the use of slings or other similar support means, while selectively disassembling modules, to support the modules extending outward from the side of the horizontal support means opposite to that side from which modules are being removed. Stated differently in FIGS. 4 through 6, if the modules extending to the right are to be removed, then slings will have to be used to support the modules which extend to the left of the horizontal support means 20.

Although the support system which has been described has been applicable for demister systems with two levels of modules, it should be apparent from the description that such a system is easily adaptable to provide support for modules stacked in more than two levels. This may be accomplished for the preferred embodiment by providing another group of vertical support means which extend downward from the horizontal support means further than either of the vertical support bars 26 or 32, 34; or for the alternative embodiments, by providing longer vertical support rods to which more channel washers are mounted to provide additional levels of holding assemblies.

Further, it should be apparent that although the elements shown are substantially constructed of metal, it is also possible to use other materials which provide the requisite strength and durability to withstand the high gas temperatures and corrosive atmosphere inherent in an air pollution control system. Such a material may be reinforced plastic which has proven to be an economical and equally sufficient material for use in air pollution control systems.

From the foregoing it is apparent that there is provided a suspension system for supporting a plurality of individual vertically stacked modules which permit future selective disassembly of the modules from the support system. This is accomplished by providing a plurality of vertical support means supported from at least two laterally spaced horizontal support means and to which are mounted a plurality of retaining means and resting means. The retaining means and resting means are oriented relative to one another to provide at least two levels of holding assemblies in which modules are held between the respective retaining and resting means. The modules may be selectively disassembled from the support system by permitting at least one set of retaining means to be vertically movable relative to its respective set of resting means, the modules thereby being released from retention by the retaining means and resting means.

While these embodiments of the invention have been shown and described, it will be understood that it is merely illustrative and that changes may be made without departing from the scope of the invention as claimed.

What is claimed is:

1. An apparatus for supporting vertically stacked modules comprising:

a horizontally disposed longitudinally extending support;

a first vertically extending support integrally attached to and extending downward from said horizontal support;

a second vertically extending support removably supported from and extending downward from said horizontal support a greater distance than said first vertical support;

first retaining means mounted on said first vertical support at a first vertical elevation from said horizontal support;

second retaining means mounted on said second vertical support at a second vertical elevation from said horizontal support, said second vertical elevation being vertically below said first vertical elevation;

a first resting surface means mounted on said second vertical support at'a third vertical elevation from said horizontal support, said third vertical elevation being vertically between said first and second vertical elevations;

a second resting surface means mounted on said second vertical support at a fourth vertical elevation from said horizontal support, said fourth vertical elevation being vertically below said second vertical elevation;

said first retaining means and first resting surface means forming a first holding assembly and said second retaining means and second resting surface means forming a second holding assembly vertically below said first holding assembly, said holding assemblies each supporting at least one of the modules between its respective retaining means and resting surface means; and

said second vertical support being detachable from said horizontal support to vertically move said first resting surface means relative to said first retaining means to release said module supported therebetween.

2. The apparatus of claim 1 wherein said horizontal support comprises two parallel longitudinally extending beams laterally spaced apart, wherein said second vertical support extends upward between said beams in said lateral space and wherein there is provided a pin which passes transversely through said second vertical support and extends across said lateral space between said beams to support said second vertical support from said beams, said pin being removable from said second vertical support to permit detachment of said second vertical support from said beams.

3. The apparatus of claim 2 wherein said first and second retaining means comprise clips which extend laterally outward from said vertical supports and which have downwardly extending lips, and wherein said first and second resting surfaces means comprise horizontal rails affixed to said second vertical support which extend laterally outward therefrom.

4. A demister vane suspension system for supporting levels of demister vane modules in an air pollution control system, the modules being arranged in longitudinally extending rows and each having mounting means at the lateral ends thereof, said suspension system comprising;

a plurality of longitudinally extending horizontal supports disposed in parallel fashion at a predetermined elevation in the air pollution control system, said horizontal supports being laterally spaced a distance substantially equal to the lateral dimension of said modules;

a first and second plurality of vertically extending supports extending downward from and supported by each of said horizontal supports, said vertical supports being spaced along the longitudinal length of each of said horizontal supports to provide a plurality of groups therealong each of which includes at least two of each of said first and second plurality of vertical supports;

an upper retaining means mounted on each of said vertical supports of said first plurality at a first vertical elevation from said horizontal supports;

an upper resting surface means, a lower retaining means and a lower resting surface means mounted on each of said vertical supports of said second plurality at a second vertical elevation, a third vertical elevation and a fourth vertical elevation from said horizontal supports respectively, said second vertical elevation being vertically below said first vertical elevation, said third vertical elevation being vertically below said second vertical elevation and said fourth vertical elevation being vertically below said third vertical elevation;

said modules being supported between two of said horizontal supports by one of said groups of vertical supports on one of said two horizontal supports and by one of said groups of vertical supports on the other of said two horizontal supports, said modules of one level being retained between corresponding upper retaining means and upper resting surfaces means of one of said groups of vertical supports and said modules of another level being retained between corresponding lower retaining means and lower resting surfaces means of one of said groups of vertical supports; and

said vertical supports of said first plurality each being integrally attached to said horizontal supports and said vertical supports of said second plurality each being removably supported from said horizontal supports whereby said modules retain between said upper retaining means and upper resting surfaces means may be released from therebetween by detaching said vertical supports of said second plurality from said horizontal supports.

5. The suspension system of claim 4 wherein said resting surfaces means of each of said groups of vertical supports are integrally attached to all of said second plurality of vertical supports of said group.

6. The suspension system of claim 5 wherein each of said horizontal supports is comprised of two channelled beams longitudinally extending and laterally spaced apart and wherein each of said vertical supports of said second plurality extends through said lateral spacing between said two channelled beams and is supported therefrom by a retaining pin which passes through said vertical support and extends across the opening formed by said lateral spacing.

7. The suspension system of claim 6 wherein each of said vertical supports of said first and second plurality is a bar, wherein said resting surfaces means are rails which extend laterally outward from and which are integrally attached to all of said bars of said second plurality in each of said groups of said vertical supports, and wherein said retaining means are retaining clips which extend laterally outward from and which are each integrally attached to only one of said bars of said first and second plurality, each of said retaining clips having downwardly extending lips.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION PATENT N0. 3,87o, r87

DATED 2 March 11, 1975 INVENTORtS) William Barrett Hurlbut, sr. et a].

It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Under Inventors: before "Gerald Maurin," insert "Peter-- Signed and Sealed this fourth Day of May 1976 [SEAL] Allen.

RUTH C. M A SON C. MARSHALL DANN Alteslmg ()jjrcer (ummissiuncr nj'lumuls and Trademarks 

1. An apparatus for supporting vertically stacked modules comprising: a horizontally disposed longitudinally extending support; a first vertically extending support integrally attached to and extending downward from said horizontal support; a second vertically extending support removably supported from and extending downward from said horizontal support a greater distance than said first vertical support; first retaining means mounted on said first vertical support at a first vertical elevation from said horizontal support; second retaining means mounted on said second vertical support at a second vertical elevation from said horizontal support, said second vertical elevation being vertically below said first vertical elevation; a first resting surface means mounted on said second vertical support at a third vertical elevation from said horizontal support, said third vertical elevation being vertically between said first and second vertical elevations; a second resting surface means mounted on said second vertical support at a fourth vertical elevation from said horizontal support, said fourth vertical elevation being vertically below said second vertical elevation; said first retaining means and first resting surface means forming a first holding assembly and said second retaining means and second resting surface means forming a second holding assembly vertically below said first holding assembly, said holding assemblies each supporting at least one of the modules between its respective retaining means and resting surface means; and said second vertical support being detachable from said horizontal support to vertically move said first resting surface means relative to said first retaining means to release said module supported therebetween.
 1. An apparatus for supporting vertically stacked modules comprising: a horizontally disposed longitudinally extending support; a first vertically extending support integrally attached to and extending downward from said horizontal support; a second vertically extending support removably supported from and extending downward from said horizontal support a greater distance than said first vertical support; first retaining means mounted on said first vertical support at a first vertical elevation from said horizontal support; second retaining means mounted on said second vertical support at a second vertical elevation from said horizontal support, said second vertical elevation being vertically below said first vertical elevation; a first resting surface means mounted on said second vertical support at a third vertical elevation from said horizontal support, said third vertical elevation being vertically between said first and second vertical elevations; a second resting surface means mounted on said second vertical support at a fourth vertical elevation from said horizontal support, said fourth vertical elevation being vertically below said second vertical elevation; said first retaining means and first resting surface means forming a first holding assembly and said second retaining means and second resting surface means forming a second holding assembly vertically below said first holding assembly, said holding assemblies each supporting at least one of the modules between its respective retaining means and resting surface means; and said second vertical support being detachable from said horizontal support to vertically move said first resting surface means relative to said first retaining means to release said module supported therebetween.
 2. The apparatus of claim 1 wherein said horizontal support comprises two parallel longitudinally extending beams laterally spaced apart, wherein said second vertical support extends upward between said beams in said lateral space and wherein there is provided a pin which passes transversely through said second vertical support and extends across said lateral space between said beams to support said second vertical support from said beams, said pin being removable from said second vertical support to permit detachment of said second vertical support from said beams.
 3. The apparatus of claim 2 wherein said first and second retaining means comprise clips which extend laterally outward from said vertical supports and which have downwardly extending lips, and wherein said first and second resting surfaces means comprise horizontal rails affixed to said second vertical support which extend laterally outward therefrom.
 4. A demister vane suspension system for supporting levels of demister vane modules in an air pollution control system, the modules being arranged in longitudinally extending rows and each having mounting means at the lateral ends thereof, said suspension system comprising; a plurality of longitudinally extending horizontal supports disposed in parallel fashion at a predetermined elevation in the air pollution control system, said horizontal supports being laterally spaced a distance substantially equal to the lateral dimension of said modules; a first and second plurality of vertically extending supports extending downward from and supported by each of said horizontal supports, said vertical supports being spaced along the longitudinal length of each of said horizontal supports to provide a plurality of groups therealong each of which includes at least two of each of said first and second plurality of vertical supports; an upper retaining means mounted on eAch of said vertical supports of said first plurality at a first vertical elevation from said horizontal supports; an upper resting surface means, a lower retaining means and a lower resting surface means mounted on each of said vertical supports of said second plurality at a second vertical elevation, a third vertical elevation and a fourth vertical elevation from said horizontal supports respectively, said second vertical elevation being vertically below said first vertical elevation, said third vertical elevation being vertically below said second vertical elevation and said fourth vertical elevation being vertically below said third vertical elevation; said modules being supported between two of said horizontal supports by one of said groups of vertical supports on one of said two horizontal supports and by one of said groups of vertical supports on the other of said two horizontal supports, said modules of one level being retained between corresponding upper retaining means and upper resting surfaces means of one of said groups of vertical supports and said modules of another level being retained between corresponding lower retaining means and lower resting surfaces means of one of said groups of vertical supports; and said vertical supports of said first plurality each being integrally attached to said horizontal supports and said vertical supports of said second plurality each being removably supported from said horizontal supports whereby said modules retain between said upper retaining means and upper resting surfaces means may be released from therebetween by detaching said vertical supports of said second plurality from said horizontal supports.
 5. The suspension system of claim 4 wherein said resting surfaces means of each of said groups of vertical supports are integrally attached to all of said second plurality of vertical supports of said group.
 6. The suspension system of claim 5 wherein each of said horizontal supports is comprised of two channelled beams longitudinally extending and laterally spaced apart and wherein each of said vertical supports of said second plurality extends through said lateral spacing between said two channelled beams and is supported therefrom by a retaining pin which passes through said vertical support and extends across the opening formed by said lateral spacing. 